How to create String.Index with _rawBits? / How to retrieve String.Index from _RegexParser.Diagnostic.Behavior.error

Using Swift
1

I create Regex by a rather long regular expression, but it gives me the following error:

Printing description of error:
▿ expected '''
  ▿ error : expected '''
    ▿ diag : Diagnostic
      - behavior : _RegexParser.Diagnostic.Behavior.error
      - message : "expected \'\'\'"
      ▿ location : Location
        ▿ range : Range(Swift.String.Index(_rawBits: 1310983)..<Swift.String.Index(_rawBits: 1310983))
          ▿ lowerBound : Index
            - _rawBits : 1310983
          ▿ upperBound : Index
            - _rawBits : 1310983
      ▿ underlyingParseError : Optional<ParseError>
        ▿ some : expected '''
          - expected : "\'"
  ▿ location : Location
    ▿ range : Range(Swift.String.Index(_rawBits: 1310983)..<Swift.String.Index(_rawBits: 1310983))
      ▿ lowerBound : Index
        - _rawBits : 1310983
      ▿ upperBound : Index
        - _rawBits : 1310983

And I'm trying to locate the location of the statement through this error, but I can't find how to create a specific Index with this _rawBits, and there's no way to get the location out of this error.

2

Ok I retrieve it through the Mirror:

let location = Mirror(reflecting: error).children.first { (label, value) in label == "location" }!.value
let range = Mirror(reflecting: location).children.first { (label, value) in label == "range" }!.value as! Range<String.Index>